A new laser pyroelectric control circuit

Abstract

The application relates to the technical field of laser equipment, and particularly discloses a novel laser pyroelectric control circuit, which comprises a temperature difference discharge sheet, a same-ratio amplification circuit, a filter circuit, a peak value holding circuit, a pulse detection circuit and a single-chip microcomputer; the temperature difference discharge sheet, the same-ratio amplification circuit, the filter circuit, the peak value holding circuit and the single-chip microcomputer are sequentially connected; and the pulse detection circuit is connected with the filter circuit and the single-chip microcomputer respectively. The novel laser pyroelectric control circuit provided by the application can convert the temperature difference into a voltage signal by collecting the heat of known laser on the temperature difference discharge sheet, amplify the voltage signal, perform low-pass filtering and high-pass filtering on the voltage signal, and then pass the voltage signal through the peak value holding circuit, so that the single-chip microcomputer can capture and collect the signal; the collected signal is calculated by the single-chip microcomputer to obtain a power value, so that the verification purpose is achieved; and the circuit is simple, convenient and practical.

Description

Technical Field

[0001] This invention relates to the field of laser equipment technology, and more specifically, to a novel laser pyroelectric control circuit. Background Technology

[0002] Currently, most medical aesthetic equipment is laser equipment used for hair removal, skin rejuvenation, freckle removal, etc. To prevent irreversible damage to the treatment area caused by a mismatch between the laser output energy and the actual output energy, a laser energy meter is embedded in the machine to verify the stability of the output laser energy and to calibrate the output treatment energy.

[0003] This type of energy meter is not only expensive but also bulky, affecting the aesthetics of the equipment. Therefore, designing an energy meter control circuit that is compatible with laser equipment is an inevitable trend. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a novel laser pyroelectric control circuit that utilizes the voltage change of a thermoelectric discharge plate, processes and calculates this voltage, and then calibrates the input laser power. The circuit is simple, convenient, and practical.

[0005] As a first aspect of the present invention, a novel laser pyroelectric control circuit is provided, comprising a thermoelectric discharge sheet, a proportional amplifier circuit, a filter circuit, a peak hold circuit, a pulse detection circuit, and a microcontroller, wherein the thermoelectric discharge sheet, the proportional amplifier circuit, the filter circuit, the peak hold circuit, and the microcontroller are connected in sequence, and the pulse detection circuit is connected to the filter circuit and the microcontroller respectively.

[0006] The thermoelectric discharge sheet is used to acquire an initial voltage signal and output the acquired initial voltage signal to the proportional amplifier circuit.

[0007] The proportional amplifier circuit is used to amplify the initial voltage signal proportionally and output the amplified voltage signal to the filter circuit.

[0008] The filtering circuit is used to filter the amplified voltage signal and output the filtered voltage signal to the peak holding circuit and the pulse detection circuit respectively.

[0009] The peak hold circuit is used to hold the peak of the filtered voltage signal to output a peak hold voltage signal.

[0010] The pulse detection circuit is used to compare the filtered voltage with a preset reference voltage. When the filtered voltage is greater than the reference voltage, a spike pulse signal is output to the microcontroller.

[0011] The microcontroller, upon receiving the spike pulse signal output by the pulse detection circuit, begins to acquire the peak hold voltage signal output by the peak hold circuit, and then outputs a discharge control signal to the analog switch in the peak hold circuit to control the analog switch to discharge the peak hold voltage.

[0012] Furthermore, it also includes a power supply circuit, which is connected to the proportional amplifier circuit, the filter circuit and the peak hold circuit respectively, for supplying power to the novel laser pyroelectric control circuit.

[0013] Furthermore, the proportional amplifier circuit includes an operational amplifier U1, matching resistors R5, R9, and R13, capacitor C9, and capacitor C10. The initial voltage signal POWER+ enters the non-inverting input terminal +IN of the operational amplifier U1 through the matching resistor R5. The inverting input terminal -IN of the operational amplifier U1 is connected to one end of resistor R9 and one end of resistor R13, respectively. The other end of resistor R13 is grounded, and the other end of resistor R9 is connected to the output terminal VOUT of the operational amplifier U1. The initial voltage signal POWER+ is amplified by 6 times through the non-inverting resistors R9 and R13. The +12V input voltage of the operational amplifier U1 is filtered by capacitors C9 and C10.

[0014] Furthermore, the filtering circuit includes an operational amplifier U4, an RC low-pass filter circuit, and a high-pass filter circuit. The amplified voltage signal OUT is filtered by a current-limiting resistor R10 and a capacitor C16, and then enters the non-inverting input terminal 1IN+ of the operational amplifier U4. It is directly output by the operational amplifier U4 to resistor R4, then through the RC low-pass filter circuit composed of resistor R1 and capacitor C7, and then through the non-inverting input terminal 4IN+ of the operational amplifier U4 to resistor R3. After passing through the high-pass filter circuit composed of capacitor C13 and resistor R16, it enters the non-inverting input terminal 2IN+ of the operational amplifier U4, and then through resistor R17 to enter the non-inverting input terminal 3IN+ of the operational amplifier U4. The inverting input terminal 3IN- of the operational amplifier U4 is connected to resistor R14, resistor R11, and potentiometer R6. Potentiometer R6 is connected to the output terminal 3OUT, and after passing through the filtering circuit composed of resistor R15 and capacitor C20, the filtered voltage signal OUT2 is output.

[0015] Furthermore, the peak hold circuit includes operational amplifier U2, transistor V1, operational amplifier U3, and analog switch IC1. The filtered voltage signal OUT2 is connected to the non-inverting input terminal +IN of operational amplifier U2. The inverting input terminal -IN of operational amplifier U2 is connected to the microcontroller pin P_POWER2 through resistor R2. The output terminal VOUT of operational amplifier U2 is connected to resistor R7 and transistor V1. The collector of transistor V1 is connected to a 12V power supply filtered by capacitors C11 and C12. The source voltage is connected to the emitter of transistor V1 via resistor R12 and capacitor C19, and then via resistor R8 to the non-inverting input terminal +IN of operational amplifier U3. The inverting input terminal -IN of operational amplifier U3 is connected to the pin P_POWER2 of the microcontroller. The output terminal VOUT of operational amplifier U3 is connected to the pin P_POWER2 of the microcontroller. The emitter of transistor V1 is also connected to analog switch IC1, which is controlled by the pin FD_CONTROL of the microcontroller.

[0016] The operational amplifier U2 amplifies the voltage difference between the input filtered voltage signal OUT2 and the output peak-hold voltage signal P_POWER2. When the peak-hold voltage signal P_POWER2 is less than the filtered voltage signal OUT2, the operational amplifier U2 outputs a positive voltage, the transistor V1 is turned on, and the capacitor C19 is charged. When the peak-hold voltage signal P_POWER2 is greater than the filtered voltage signal OUT2, the operational amplifier U2 outputs a reverse voltage, the transistor V1 is turned off, and the voltage of the capacitor C19 cannot change abruptly. The microcontroller controls the analog switch IC1 to discharge the peak-hold voltage.

[0017] Furthermore, the pulse detection circuit includes a comparator U5, resistors R20, R21, and R22, capacitors C24, C25, and C26. A voltage divider is established between resistors R21 and R22, with the voltage across R22 serving as a reference voltage. This reference voltage is connected to the positive input terminal 1IN+ of the comparator U5, and the filtered voltage signal OUT2 is connected to the inverting input terminal 1IN- of the comparator U5 for comparison.

[0018] The spike pulse signal P_CHECK2 is output to the microcontroller, and capacitors C24 and C25 are filter capacitors for the power input.

[0019] Furthermore, the thermoelectric discharge sheet is connected to the proportional amplifier circuit via the pyroelectric acquisition interface JP1.

[0020] Furthermore, the microcontroller is connected to the peak hold circuit, the pulse detection circuit, and the power supply circuit via the control interface JP2.

[0021] The novel laser pyroelectric control circuit provided by this invention has the following advantages: it utilizes the voltage change of the thermoelectric discharge plate, processes and calculates the voltage, and then calibrates the input laser power. The circuit is simple, convenient and practical, and is more compact and cheaper than commercially available laser energy meters. Attached Figure Description

[0022] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof.

[0023] Figure 1 The schematic diagram of the novel laser pyroelectric control circuit provided by the present invention.

[0024] Figure 2 A schematic diagram of the overall structure of the novel laser pyroelectric control circuit provided by the present invention.

[0025] Figure 3 A schematic diagram of the power supply circuit provided by the present invention.

[0026] Figure 4 A schematic diagram of the proportional amplifier circuit provided by the present invention.

[0027] Figure 5 This is a schematic diagram of the filter circuit provided by the present invention.

[0028] Figure 6 A schematic diagram of the peak hold circuit provided by the present invention.

[0029] Figure 7 This is a schematic diagram of the circuit structure of the pulse detection circuit provided by the present invention.

[0030] Figure 8 A schematic diagram of the circuit structure of the pyroelectric acquisition interface provided by the present invention.

[0031] Figure 9 A schematic diagram of the circuit structure of the microcontroller control interface provided by the present invention. Detailed Implementation

[0032] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of the novel laser pyroelectric control circuit proposed according to the present invention. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0033] This embodiment provides a novel laser pyroelectric control circuit, such as Figure 1-2 As shown, the novel laser pyroelectric control circuit includes a thermoelectric discharge sheet, a proportional amplifier circuit, a filter circuit, a peak hold circuit, a pulse detection circuit, and a microcontroller. The thermoelectric discharge sheet, the proportional amplifier circuit, the filter circuit, the peak hold circuit, and the microcontroller are connected in sequence, and the pulse detection circuit is connected to the filter circuit and the microcontroller respectively.

[0034] The thermoelectric discharge sheet is used to acquire an initial voltage signal and output the acquired initial voltage signal to the proportional amplifier circuit.

[0035] The proportional amplifier circuit is used to amplify the initial voltage signal proportionally and output the amplified voltage signal to the filter circuit.

[0036] The filtering circuit is used to filter the amplified voltage signal and output the filtered voltage signal to the peak holding circuit and the pulse detection circuit respectively.

[0037] The peak hold circuit is used to hold the peak of the filtered voltage signal to output a peak hold voltage signal.

[0038] The pulse detection circuit is used to compare the filtered voltage with a preset reference voltage. When the filtered voltage is greater than the reference voltage, a spike pulse signal is output to the microcontroller.

[0039] The microcontroller, upon receiving the spike pulse signal output by the pulse detection circuit, begins to acquire the peak hold voltage signal output by the peak hold circuit, and then outputs a discharge control signal to the analog switch in the peak hold circuit to control the analog switch to discharge the peak hold voltage.

[0040] It should be noted that when a laser is applied to a thermoelectric discharge sheet, the pyroelectric effect of the thermoelectric discharge sheet means that the change in temperature causes a voltage to appear across the material, and the initial voltage signal is collected.

[0041] Specifically, a thermoelectric discharge sheet generates electricity by utilizing the temperature difference between its upper and lower layers. The temperature difference changes of lasers output from lasers of different power levels are converted into voltage changes.

[0042] Place the thermoelectric discharge plate between the heat source and the cold source, and tighten it with bolts (air pressure is best to avoid thermal short circuits). Power generation is achieved simply by establishing a temperature difference between the heat source and the cold source. To ensure a sufficiently large power output, note the following:

[0043] (1) Cold and heat sources must press the generator tightly. The power generation is related to the pressure. The higher the pressure, the greater the power generation.

[0044] (2) If possible, keep the temperature of the cold source as low as possible. Under the same temperature difference, the lower the temperature of the cold source, the greater the power generation.

[0045] (3) The load should be matched.

[0046] Preferably, such as Figure 3 As shown, it also includes a power supply circuit, which is connected to the proportional amplifier circuit, the filter circuit and the peak hold circuit respectively, and is used to supply power to the novel laser pyroelectric control circuit.

[0047] Preferably, such as Figure 4 As shown, the proportional amplifier circuit includes an operational amplifier U1, matching resistors R5, R9, and R13, capacitor C9, and capacitor C10. The initial voltage signal POWER+ enters the non-inverting input terminal +IN of the operational amplifier U1 through the matching resistor R5. The inverting input terminal -IN of the operational amplifier U1 is connected to one end of resistor R9 and one end of resistor R13. The other end of resistor R13 is grounded. The other end of resistor R9 is connected to the output terminal VOUT of the operational amplifier U1. The initial voltage signal POWER+ is amplified by a factor of 6 through resistors R9 and R13 in a non-inverting manner. The matching resistor R5 makes the sampled voltage close to the actual voltage. Amplification factor: The amplified output signal is OUT. The +12V input voltage of the operational amplifier U1 is filtered by capacitors C9 and C10 to remove noise from the operational amplifier.

[0048] To reduce the impact of high-frequency and low-frequency components on waveform purity and enhance the signal's anti-interference capability, a second-order low-pass and high-pass filter circuit was designed, as follows:

[0049] like Figure 5As shown, the filtering circuit includes an operational amplifier U4, an RC low-pass filter circuit, and a high-pass filter circuit. The amplified voltage signal OUT is filtered by a current-limiting resistor R10 and a capacitor C16, and then enters the non-inverting input terminal 1IN+ of the operational amplifier U4. It is directly output by the operational amplifier U4 to resistor R4, then through the RC low-pass filter circuit composed of resistor R1 and capacitor C7, and then through the non-inverting input terminal 4IN+ of the operational amplifier U4 to resistor R3. After passing through the high-pass filter circuit composed of capacitor C13 and resistor R16, it enters the non-inverting input terminal 2IN+ of the operational amplifier U4, and then through resistor R17 to enter the non-inverting input terminal 3IN+ of the operational amplifier U4. The inverting input terminal 3IN- of the operational amplifier U4 is connected to resistor R14, resistor R11, and potentiometer R6. Potentiometer R6 is connected to the output terminal 3OUT, and after passing through the filter circuit composed of resistor R15 and capacitor C20, the filtered voltage signal OUT2 is output.

[0050] Low-pass filter upper cutoff frequency: f PL =1 / 2πR1C7≈100HZ;

[0051] High-pass filter lower cutoff frequency: f PH =1 / 2πR 16 C 13 ≈7Hz.

[0052] Below is the correspondence between the low-pass filter cutoff frequency and capacitor C7:

[0053] <![CDATA[f p (Hz)]]> C(μF) <![CDATA[f p (Hz)]]> C(pF) 1～10 20～1 <![CDATA[10 3 ~10 4 ]]> <![CDATA[10 4 ~10 3 ]]> <![CDATA[10~10 2 ]]> 1～0.1 <![CDATA[10 4 ~10 5 ]]> <![CDATA[10 3 ~10 2 ]]> <![CDATA[10 2 ~10 3 ]]> 0.1～0.01 <![CDATA[10 5 ~10 6 ]]> <![CDATA[10 2 ~10]]>

[0054] Below is the relationship between the high-pass filter cutoff frequency and capacitor C13:

[0055] <![CDATA[f p (Hz)]]> C(μF) <![CDATA[f p (Hz)]]> C(pF) 1～10 20～1 <![CDATA[10 3 ~10 4 ]]> <![CDATA[10 4 ~10 3 ]]> <![CDATA[10~10 2 ]]> 1～0.1 <![CDATA[10 4 ~10 5 ]]> <![CDATA[10 3 ~10 2 <!-- 4 -->]]> <![CDATA[10 2 ~10 3 ]]> 0.1～0.01 <![CDATA[10 5 ~10 6 ]]> <![CDATA[10 2 ~10]]>

[0056] We can make corresponding designs according to actual requirements.

[0057] Because the output waveform of the filter circuit is a spike pulse waveform, it is difficult for the microcontroller to capture the signal. Therefore, a hysteresis method is used to boost the voltage and compensate for this defect. A peak hold circuit is designed to provide the voltage signal to the microcontroller. The circuit design is as follows:

[0058] like Figure 6As shown, the peak hold circuit includes operational amplifier U2, transistor V1, operational amplifier U3, and analog switch IC1. The filtered voltage signal OUT2 is connected to the non-inverting input terminal +IN of operational amplifier U2. The inverting input terminal -IN of operational amplifier U2 is connected to the microcontroller pin P_POWER2 through resistor R2. The output terminal VOUT of operational amplifier U2 is connected to resistor R7 and transistor V1. The collector of transistor V1 is connected to a 12V power supply filtered by capacitors C11 and C12. The voltage is connected to the emitter of transistor V1 via resistor R12 and capacitor C19, and then via resistor R8 to the non-inverting input terminal +IN of operational amplifier U3. The inverting input terminal -IN of operational amplifier U3 is connected to the pin P_POWER2 of the microcontroller. The output terminal VOUT of operational amplifier U3 is connected to the pin P_POWER2 of the microcontroller. The emitter of transistor V1 is also connected to analog switch IC1, which is controlled by the pin FD_CONTROL of the microcontroller.

[0059] The operational amplifier U2 amplifies the voltage difference between the input filtered voltage signal OUT2 and the output peak-hold voltage signal P_POWER2. When the peak-hold voltage signal P_POWER2 is less than the filtered voltage signal OUT2, the operational amplifier U2 outputs a positive voltage, the transistor V1 is turned on, and the capacitor C19 is charged. When the peak-hold voltage signal P_POWER2 is greater than the filtered voltage signal OUT2, the operational amplifier U2 outputs a reverse voltage, the transistor V1 is turned off, and the voltage of the capacitor C19 cannot change abruptly. The microcontroller controls the analog switch IC1 to discharge the peak-hold voltage.

[0060] Among them, capacitor C19 is a polystyrene capacitor with a capacitance range of 100pF-0.01uF, a negative temperature coefficient, an insulation resistance of up to 100GΩ, and extremely low leakage current.

[0061] It should be noted that the slew rate SR of the subsequent op-amp U3 is specifically reduced to compensate for the slew rate of the preceding op-amp U2. The circuit primarily relies on op-amp U2 for capture, so its slew rate SR should be as high as possible. Op-amp U3 plays a compensating role, and its slew rate SR cannot be too low either. Therefore, the high-speed operational amplifier AD820 is chosen for both.

[0062] Preferably, such as Figure 7As shown, the pulse detection circuit includes comparator U5, resistors R20, R21, and R22, capacitors C24, C25, and C26. The purpose of this circuit is to detect the presence of a spike pulse input and feed the result back to the microcontroller. Through voltage division by resistors R21 and R22, the voltage across resistor R22 serves as a reference voltage. This reference voltage is connected to the positive input terminal 1IN+ of comparator U5, and the filtered voltage signal OUT2 is connected to the negative input terminal 1IN- of comparator U5. The two are compared, and the spike pulse signal P_CHECK2 is output to the microcontroller. The microcontroller performs corresponding processing, which is equivalent to an enable signal for peak voltage acquisition, thus playing the role of spike pulse detection. Capacitors C24 and C25 are filter capacitors for the power input.

[0063] Preferably, such as Figure 8 As shown, the thermoelectric discharge sheet is connected to the proportional amplifier circuit via the pyroelectric acquisition interface JP1.

[0064] Preferably, such as Figure 9 As shown, the microcontroller is connected to the peak hold circuit, pulse detection circuit and power supply circuit through the control interface JP2.

[0065] The working principle of the novel laser pyroelectric control circuit provided by this invention is as described above and will not be repeated here.

[0066] The novel laser pyroelectric control circuit provided by this invention collects voltage through a thermoelectric discharge plate, and calculates the thermal power using a microcontroller after passing through a proportional amplification circuit, a low-pass filter, a high-pass filter circuit, a peak hold circuit, and a spike pulse detection circuit. It is mainly used for energy calibration of laser pulse output devices. By collecting the known heat of the laser on the thermoelectric discharge plate, the temperature difference is converted into a voltage signal. The voltage signal is amplified, low-pass filtered, and high-pass filtered, and then passed through a peak hold circuit to facilitate signal capture and acquisition by the microcontroller. The collected signal is used by the microcontroller to calculate the power value, and can also be displayed on a host computer screen to achieve the purpose of verification.

[0067] Figure 1-7 The functional descriptions of the main components in the circuit schematic are shown in the table below:

[0068]

[0069]

[0070] Figure 8-9 The functional descriptions of the main components in the circuit schematic are shown in the table below:

[0071]

[0072] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A novel laser pyroelectric control circuit, characterized in that, It includes a thermoelectric discharge sheet, a proportional amplifier circuit, a filter circuit, a peak hold circuit, a pulse detection circuit, and a microcontroller. The thermoelectric discharge sheet, the proportional amplifier circuit, the filter circuit, the peak hold circuit, and the microcontroller are connected in sequence. The pulse detection circuit is connected to the filter circuit and the microcontroller respectively. The thermoelectric discharge sheet is used to acquire an initial voltage signal and output the acquired initial voltage signal to the proportional amplifier circuit. The proportional amplifier circuit is used to amplify the initial voltage signal proportionally and output the amplified voltage signal to the filter circuit. The filtering circuit is used to filter the amplified voltage signal and output the filtered voltage signal to the peak holding circuit and the pulse detection circuit respectively. The peak hold circuit is used to hold the peak of the filtered voltage signal to output a peak hold voltage signal. The pulse detection circuit is used to compare the filtered voltage with a preset reference voltage. When the filtered voltage is greater than the reference voltage, a spike pulse signal is output to the microcontroller. The microcontroller is used to receive the spike pulse signal output by the pulse detection circuit, start to collect the peak holding voltage signal output by the peak holding circuit, and then output a discharge control signal to the analog switch in the peak holding circuit to control the analog switch to discharge the peak holding voltage. The proportional amplifier circuit includes an operational amplifier U1, matching resistors R5, R9, and R13, capacitors C9 and C10. The initial voltage signal POWER+ enters the non-inverting input terminal +IN of the operational amplifier U1 through the matching resistor R5. The inverting input terminal -IN of the operational amplifier U1 is connected to one end of resistor R9 and one end of resistor R13. The other end of resistor R13 is grounded. The other end of resistor R9 is connected to the output terminal VOUT of the operational amplifier U1. The initial voltage signal POWER+ is amplified by 6 times through resistors R9 and R13 in a non-inverting ratio. The +12V input voltage of the operational amplifier U1 is filtered by capacitors C9 and C10. The filtering circuit includes an operational amplifier U4, an RC low-pass filter circuit, and a high-pass filter circuit. The amplified voltage signal OUT is filtered by a current-limiting resistor R10 and a capacitor C16, and then enters the non-inverting input terminal 1IN+ of the operational amplifier U4. It is directly output by the operational amplifier U4 to resistor R4, then through the RC low-pass filter circuit composed of resistor R1 and capacitor C7, and then through the non-inverting input terminal 4IN+ of the operational amplifier U4 to resistor R3. After passing through the high-pass filter circuit composed of capacitor C13 and resistor R16, it enters the non-inverting input terminal 2IN+ of the operational amplifier U4, and then through resistor R17 to enter the non-inverting input terminal 3IN+ of the operational amplifier U4. The inverting input terminal 3IN- of the operational amplifier U4 is connected to resistor R14, resistor R11, and potentiometer R6. Potentiometer R6 is connected to the output terminal 3OUT, and after passing through the filtering circuit composed of resistor R15 and capacitor C20, the filtered voltage signal OUT2 is output. The peak hold circuit includes operational amplifier U2, transistor V1, operational amplifier U3, and analog switch IC1. The filtered voltage signal OUT2 is connected to the non-inverting input +IN of operational amplifier U2. The inverting input -IN of operational amplifier U2 is connected to the microcontroller pin P_POWER2 via resistor R2. The output VOUT of operational amplifier U2 is connected to resistor R7 and transistor V1. The collector of transistor V1 is connected to a 12V power supply voltage filtered by capacitors C11 and C12. The emitter of transistor V1 is connected to resistor R12 and capacitor C19, and then connected to the non-inverting input +IN of operational amplifier U3 via resistor R8. The inverting input -IN of operational amplifier U3 is connected to the microcontroller pin P_POWER2. The output VOUT of operational amplifier U3 is connected to... The microcontroller's pin P_POWER2 and the emitter of transistor V1 are both connected to the analog switch IC1, which is controlled by the microcontroller's pin FD_CONTROL. The operational amplifier U2 amplifies the voltage difference between the input filtered voltage signal OUT2 and the output peak-hold voltage signal P_POWER2. When the peak-hold voltage signal P_POWER2 is less than the filtered voltage signal OUT2, the operational amplifier U2 outputs a positive voltage, transistor V1 conducts, and capacitor C19 is charged. When the peak-hold voltage signal P_POWER2 is greater than the filtered voltage signal OUT2, the operational amplifier U2 outputs a reverse voltage, transistor V1 is cut off, and the voltage of capacitor C19 cannot change abruptly. The microcontroller controls the analog switch IC1 to discharge the peak-hold voltage. The pulse detection circuit includes a comparator U5, resistors R20, R21, and R22, and capacitors C24, C25, and C26. Resistors R21 and R22 divide the voltage, and the voltage across R22 serves as a reference voltage. This reference voltage is connected to the positive input terminal 1IN+ of the comparator U5. The filtered voltage signal OUT2 is connected to the inverting input terminal 1IN- of the comparator U5. The two signals are compared, and the spike pulse signal P_CHECK2 is output to the microcontroller. Capacitors C24 and C25 are power input filter capacitors.

2. The novel laser pyroelectric control circuit according to claim 1, characterized in that, It also includes a power supply circuit, which is connected to the proportional amplifier circuit, the filter circuit and the peak hold circuit respectively, and is used to supply power to the novel laser pyroelectric control circuit.

3. The novel laser pyroelectric control circuit according to claim 1, characterized in that, The thermoelectric discharge element is connected to the proportional amplifier circuit via the pyroelectric acquisition interface JP1.

4. A novel laser pyroelectric control circuit according to claim 2, characterized in that, The microcontroller is connected to the peak hold circuit, pulse detection circuit, and power supply circuit via the control interface JP2.

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